Cranberries are a major commercial crop in certain US states and Canadian provinces. Most cranberries are processed into products such as juice, sauce, and sweetened dried cranberries, with the remainder sold fresh to consumers. Cranberry sauce is regarded an indispensable part of traditional American and Canadian Thanksgiving menus and European winter festivals. Cranberries are a source of polyphenol antioxidants, phytochemicals under active research for possible benefits to the cardiovascular system, immune system and as anti-cancer agents.